Yumeng等, 什么是I-89?

I called USCIS 1-800 today, they said it showed on the screen that I need to get I-89 form done before they process my I-485. He said it's about a thumbnail fingerprint? Do you know anything about it?

Also, what does it mean if the online status writes like this:

Your I181 CREATION OF RECORD OF LAWFUL PERMANENT RESIDENCE was received on February 8, 2005. We mailed you a receipt with information about processing. It is taking between 30 and 60 days for us to process this kind of case. We will mail you a decision as soon as processing is complete.

What's I181? I am confused. Thanks in advance.